Flagler, CO 80815 Frost Dates
80815, near Flagler, CO: the frost window
Typically, the last spring freeze lands around 05/05, roughly 250 days out. Fall's first freeze usually shows up around 10/08, roughly 155 days after the last spring frost.
Flagler sits in USDA Zone 5b (-15 to -10°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
Stretching the season past the first frost
Flagler's growing season runs out in roughly 6 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
How much risk comes with planting early here
05/05 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/22 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/20 and only about 1 year in 10 sees frost after that.
Flagler against the rest of the dataset
At roughly 155 frost-free days, Flagler places 34,074 of 40,283 ZIP codes in this dataset. Within CO, it ranks 252 of 624.
Learn more
Two guides worth reading on 80815: local microclimates, on what one yard in Flagler can differ from the 80815 normal, and zone vs. frost date, on why Zone 5b and Flagler's frost date answer different questions.